Deha Umarhadi

Mr. Deha Umarhadi

Hokkaido University
orcid

Research Focus & Metrics

Academic Career Length

10Years (2017-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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7 January 2021 in Remote Sensing
Verified
Journal Article
Open access
PDF file
RARam Avtar
Ram Avtar
DSDeepak Singh
Deepak Singh
DUDeha Umarhadi
Deha Umarhadi
YunusAli PulpadanYunusAli Pulpadan
YunusAli Pulpadan
Prakhar MisraPrakhar Misra
Prakhar Misra
KPKbvn Phanindra
Kbvn Phanindra
The COVID-19 related lockdowns have brought the planet to a standstill. It has severely shrunk the global economy in the year 2020, including India. The blue economy and especially the small-scale fisheries sector in India have dwindled due to disruptions in the fish catch, market, and supply chain. This research presents the applicability of satellite data to monitor the impact of COVID-19 related lockdown on the Indian fisheries sector. Three harbors namely Mangrol, Veraval, and Vankbara situated on the north-western coast of India were selected in this study based on characteristics like harbor’s age, administrative control, and availability of cloud-free satellite images. To analyze the impact of COVID in the fisheries sector, we utilized high-resolution PlanetScope data for monitoring and comparison of “area under fishing boats” during the pre-lockdown, lockdown, and post-lockdown phases. A support vector machine (SVM) classification algorithm was used to identify the area under the boats. The classification results were complemented with socio-economic data and ground-level information for understanding the impact of the pandemic on the three sites. During the peak of the lockdown, it was found that the “area under fishing boats” near the docks and those parked on the land area increased by 483%, 189%, and 826% at Mangrol, Veraval, and Vanakbara harbor, respectively. After phase-I of lockdown, the number of parked vessels decreased, yet those already moved out to the land area were not returned until the south-west monsoon was over. A quarter of the annual production is estimated to be lost at the three harbors due to lockdown. Our last observation (September 2020) result shows that regular fishing activity has already been re-established in all three locations. PlanetScope data with daily revisit time has a higher potential to be used in the future and can help policymakers in making informed decisions vis-à-vis the fishing industry during an emergency situation like COVID-19.

17 September 2020 in Remote Sensing
Verified
Journal Article
Open access
PDF file
RARam Avtar
Ram Avtar
Stanley Anak SuabStanley Anak Suab
Stanley Anak Suab
MSMohd Shahrizan Syukur
Mohd Shahrizan Syukur
Alexius KoromAlexius Korom
Alexius Korom
DUDeha Umarhadi
Deha Umarhadi
YunusAli PulpadanYunusAli Pulpadan
YunusAli Pulpadan
The information on biophysical parameters—such as height, crown area, and vegetation indices such as the normalized difference vegetation index (NDVI) and normalized difference red edge index (NDRE)—are useful to monitor health conditions and the growth of oil palm trees in precision agriculture practices. The use of multispectral sensors mounted on unmanned aerial vehicles (UAV) provides high spatio-temporal resolution data to study plant health. However, the influence of UAV altitude when extracting biophysical parameters of oil palm from a multispectral sensor has not yet been well explored. Therefore, this study utilized the MicaSense RedEdge sensor mounted on a DJI Phantom–4 UAV platform for aerial photogrammetry. Three different close-range multispectral aerial images were acquired at a flight altitude of 20 m, 60 m, and 80 m above ground level (AGL) over the young oil palm plantation area in Malaysia. The images were processed using the structure from motion (SfM) technique in Pix4DMapper software and produced multispectral orthomosaic aerial images, digital surface model (DSM), and point clouds. Meanwhile, canopy height models (CHM) were generated by subtracting DSM and digital elevation models (DEM). Oil palm tree heights and crown projected area (CPA) were extracted from CHM and the orthomosaic. NDVI and NDRE were calculated using the red, red-edge, and near-infrared spectral bands of orthomosaic data. The accuracy of the extracted height and CPA were evaluated by assessing accuracy from a different altitude of UAV data with ground measured CPA and height. Correlations, root mean square deviation (RMSD), and central tendency were used to compare UAV extracted biophysical parameters with ground data. Based on our results, flying at an altitude of 60 m is the best and optimal flight altitude for estimating biophysical parameters followed by 80 m altitude. The 20 m UAV altitude showed a tendency of overestimation in biophysical parameters of young oil palm and is less consistent when extracting parameters among the others. The methodology and results are a step toward precision agriculture in the oil palm plantation area.

1 April 2022 in Science of The Total Environment
Verified
Journal Article
Closed access
DUDeha Umarhadi
Deha Umarhadi
WWWirastuti Widyatmanti
Wirastuti Widyatmanti
PKPankaj Kumar
Pankaj Kumar
AYAli P. Yunus
Ali P. Yunus
KKKhaled Mohamed Khedher
Khaled Mohamed Khedher
RARam Avtar
Ram Avtar

10 August 2021 in Land Degradation & Development
Verified
Journal Article
Closed access
PDF file
DUDeha Umarhadi
Deha Umarhadi
RARam Avtar
Ram Avtar
WWWirastuti Widyatmanti
Wirastuti Widyatmanti
Brian Alan JohnsonBrian Alan Johnson
Brian Alan Johnson
AYAli P. Yunus
Ali P. Yunus
GSGulab Singh
Gulab Singh

11 March 2022 in Remote Sensing Applications: Society and Environment
Verified
Journal Article
Closed access
APAde Febri Sandhini Putri
Ade Febri Sandhini Putri
WWWirastuti Widyatmanti
Wirastuti Widyatmanti
DUDeha Umarhadi
Deha Umarhadi

8 August 2022 in Land
Verified
Journal Article
Open access
PDF file
RARam Avtar
Ram Avtar
ARApisai Vakacegu Rinamalo
Apisai Vakacegu Rinamalo
DUDeha Umarhadi
Deha Umarhadi
AGANKITA GUPTA
ANKITA GUPTA
KKKhaled Khedher
Khaled Khedher
Anjar Dimara SaktiAnjar Dimara Sakti
Anjar Dimara Sakti
This study examines land use changes and evaluates the past and projected forest carbon sequestration and its valuation in Viti Levu Island, Fiji, through a combination of remote sensing with a geospatial-based modeling approach. Land use classification was performed using Landsat 7 and Landsat 8 imageries of the years 2000 and 2020; then, cellular automata and artificial neural network (CA-ANN) modeling was conducted to predict the land use map of 2040. Carbon sequestration and the economic valuation were estimated using the land use maps of the past, present, and future (2000, 2020, and 2040) within the Integrated Valuation of Ecosystems Trade-off (InVEST) model. The results showed that deforestation occurred during the past two decades, and the forest area was predicted to keep decreasing in 2040, with the major contribution from the conversion to the agricultural area. Local communities’ perceptions confirmed that the forest conversion to croplands would persist due to the demand for fertile lands. This study estimated a loss of −7.337 megatonnes of forest carbon (Mt C) with an economic loss of USD −1369.38 million during 2000–2020 due to deforestation. If the business-as-usual scenario does not change in the near future, a potential carbon loss of −7.959 Mt C is predicted in the upcoming 20 years. The predicted results can be used to assist as a reference in establishing a national baseline and reference level for implementing the REDD+ mechanism in Fiji and sustainably managing the limited pristine forest by implementing forest-related programs.